1. Limited time only! Sign up for a free 30min personal tutor trial with Chegg Tutors
    Dismiss Notice
Dismiss Notice
Join Physics Forums Today!
The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

B Incomparable Theories

  1. Apr 16, 2018 #1
    how should incompatibile scientific theories be thought of? Newtonian mechanics and special relativity contradict each other for example, so it doesn’t make sense to just consider all scientific theories to be part of one big coherent picture.

    How do scientists think about scientific theories, particularly as it relates to different theories being incompatible and useful in different situations.
     
  2. jcsd
  3. Apr 16, 2018 #2

    ZapperZ

    User Avatar
    Staff Emeritus
    Science Advisor
    Education Advisor

    Where did you get the idea that Newtonian mechanics contradicts SR? Einstein came up with special relativity due to classical electromagnetism, not Newtonian mechanics, not being covariant under Galilean transformation. And note that SR has to match Newtonian mechanics and non-relativistic E&M at some level, because we know they work within some limits.

    Incompatible theories only mean that the phenomenon that they are trying to describe is still not well-known yet, and it is still an active research in progress. We end up with a consistent formulation on things that are well-known and established.

    Zz.
     
  4. Apr 16, 2018 #3
    I don't really believe there are incompatible theories, just different theories with different uncertainties and accuracy. In fact, almost all of Physics is (very close) approximation.
     
  5. Apr 16, 2018 #4
    Regardless of why Einstein came up with special relativity, adding velocities is performed differently in Newtonian mechanics than in special relativity as I believe you’ve mentioned. Calculations done at near light speed velocities with Newtonian mechanics give very different numbers than SR. That’s just what I mean by contradictory. I understand that Newtonian mechanics and SR agree in most situations.
     
  6. Apr 16, 2018 #5

    ZapperZ

    User Avatar
    Staff Emeritus
    Science Advisor
    Education Advisor

    But that is not the definition of contradictory, because we now know that the classical description is only a special case of a more general description. There is nothing contradictoy here.

    Zz.
     
  7. Apr 16, 2018 #6

    Dale

    Staff: Mentor

    Newtonian mechanics is part of special relativity. A part can’t contradict the whole.

    Clearly. Newtonian mechanics is the v<<c part of SR, not the near light speed part.
     
Share this great discussion with others via Reddit, Google+, Twitter, or Facebook

Have something to add?
Draft saved Draft deleted